Composite structural panel and method of fabrication

ABSTRACT

A structural panel and method of fabricating and manufacturing same comprises a top panel and a bottom panel separated by and attached to at least one, but preferably a plurality, of structural composite preforms which may be fabricated by a continuous manufacturing process and may be saturated by resin using a continuous wetting process. The composite preforms may take any cross sectional shape but are preferably trapezoidal. The top and bottom panels may be fabricated from a plurality of layers of woven fabric layers and non-woven fabric layers which are saturated with a resin that is subsequently cured using cure processes known in the art. The composite structural panel of the invention is usable as a flat structural member for use as bridge decking, ramps, trestles, and any application requiring a structural panel.

CROSS REFERENCE TO RELATED APPLICATIONS

This is document is an international application for patent filed underthe Patent Cooperation Treaty (PCT) in the Unites States ReceivingOffice (USRO), and claims the benefit of United States provisionalapplication for patent Ser. No. 62/059,143 COMPOSITE STRUCTURAL PANELAND METHOD OF FABRICATION filed in the United States Patent andTrademark Office (USPTO) under 35 U.S.C. § 111(b) on Oct. 2, 2014, whichis hereby incorporated by reference in its entirety.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

Not applicable.

INCORPORATION-BY-REFERENCE OF MATERIAL SUBMITTED ON A COMPACT DISK

Not applicable.

INCORPORATION-BY-REFERENCE OF MATERIAL FROM PUBLISHED PATENTAPPLICATIONS AND ISSUED PATENTS

United States Patent Application Publication No. US20140262011A1,published on Sep. 18, 2014 is hereby incorporated by reference in itsentirety.

U.S. Pat. No. 6,013,213, issued Jan. 11, 2000; U.S. Pat. No. 6,004,492issued Dec. 21, 1999, U.S. Pat. No. 5,897,818 issued Apr. 27, 1999; U.S.Pat. No. 5,908,591 issued Jun. 1, 1999; U.S. Pat. No. 5,429,066 issuedJul. 4, 1995; U.S. Pat. No. 5,800,749 issued Sep. 1, 1998; U.S. Pat. No.6,206,669 issued Mar. 27, 2001; U.S. Pat. No. 5,664,518 issued Sep. 9,1997; U.S. Pat. No. 6,543,469 issued Apr. 3, 2003; U.S. Pat. No.6,497,190 issued Dec. 24, 2002; and U.S. Pat. No. 6,911,252 issued Jun.28, 2005 are also incorporated herein by reference in their entirety.

United States Patent Application Publication No. US20140199551, CO-CUREDGEL COATS, ELASTOMERIC COATINGS, STRUCTURAL LAYERS, AND IN-MOLDPROCESSES FOR THEIR USE, filed in the USPTO on Jan. 16, 2013 andpublished by the USPTO on Jul. 17, 2014, is also hereby incorporated byreference in its entirety.

BACKGROUND OF THE INVENTION Field of the Invention

The field of the invention relates generally to the field of compositestructures used for bridges and other engineered structures which areintended for use in roadways, bridges, and other structures generally.More specifically, the invention relates to a composite structure foruse in engineered structures such as, for example but not limited to,bridge and other roadway decking and support structures, ramps, dockdecking and support structures, vehicle chassis and structures, trailerchassis and structures, and virtually any application which requiresstructural components; and an efficient method of fabricating same.

Background Art

The background art of engineered structures for structural panels used,for example, in bridges; bridge roadway decking; general roadwaystructures; commercial construction such as floors, walls, and roofs;and other structures typically relies upon concrete or cementfabrication techniques, including pre-stressed cement structures, tiltwall, poured-in-place, pre-fabricated or other similar concrete orcement structures. Such cement or concrete structures may beprefabricated and shipped to the construction site or may be formed andpoured in situ.

However the cement and/or concrete structures of the prior art do noteasily or economically lend themselves to methods for rapidmanufacturing, nor are they easily inspected for manufacturing flaws ordefects during fabrication. For example, a bridge structure may, overtime, develop localized points of failure within the structure that arenot visible for visual inspection, leading to failure propagation andeventual unexpected catastrophic failure of the structure. Suchstructures may contain undetectable flaws which may lay in a latentcondition for a period of years without discovery, causing severe damageor injury when they are finally subjected to a load of enough magnitudeto cause failure—which can occur, for example, during a temperatureextreme condition such as extreme cold, while supporting a high trafficload.

Furthermore, such structures, when pre-fabricated, are of such weightand volume that transport costs can be extremely high.

What is needed in the art, therefore, is an economically and easilyfabricated structure for use in applications such as, for example,bridge decking, which may be inspected at various stages of fabricationto identify flaws and defects before such structures are assembled intouse, and which lends itself to efficient, repeatable productionprocedures and techniques.

BRIEF SUMMARY OF THE INVENTION

The present invention comprises an apparatus and method that have one ormore of the following features and/or steps, which alone or in anycombination may comprise patentable subject matter.

The present invention overcomes the shortcomings of the prior art inthat it provides an economical, inspectible and efficient process forfabricating bridge and other roadway decking and support structures,ramps, dock decking and support structures, vehicle chassis andstructures, trailer chassis and structures, and virtually anyapplication which requires structural components; and an efficientmethod of fabricating same.

In accordance with one embodiment of the present invention, theinvention comprises a novel structure which may be used in anystructural application, for example, as bridge decking structure for usein bridges generally used for vehicle traffic; ramps for vehicles; orany application requiring a structural panel. The invention comprises astructural panel top half and a structural panel bottom half that mayeach be independently fabricated and then assembled and attachedtogether by, for example, adhesives and chemical bonding of any meansknown in the art, to form a unitary structural panel. The compositepreforms of the invention may be fabricated from foam surrounded byfiber cloth, which may be fiberglass, carbon fiber or any other type offiber cloth known in the art of structural composites, which is thenimpregnated with a resin. The structural panel top half may comprise aplurality of composite preforms in any cross-sectional shape, but whichmay be, preferably, a trapezoidal cross-section, which preforms may be,but are not necessarily, disposed in parallel fashion and may be but arenot necessarily equally spaced from one another, on a surface of andattached to a top plate comprised preferentially, but not necessarily,of multiple layers of fiberglass fabric material impregnated with aresin. The structural panel bottom half may comprise a plurality ofcomposite preforms in any cross-sectional shape, but which may be,preferably, a trapezoidal cross-section, which preforms may be, but arenot necessarily, disposed in parallel fashion and may be but are notnecessarily equally spaced from one another, on and attached to asurface of a bottom plate comprised preferentially, but not necessarily,of multiple layers of fabric material impregnated with a resin.

The structural preforms of the invention may be fabricated by any of themethods for continuously manufacturing a composite described in any ofU.S. Pat. No. 6,013,213, issued Jan. 11, 2000; U.S. Pat. No. 6,004,492issued Dec. 21, 1999, U.S. Pat. No. 5,897,818 issued Apr. 27, 1999; U.S.Pat. No. 5,908,591 issued Jun. 1, 1999; U.S. Pat. No. 5,429,066 issuedJul. 4, 1995; U.S. Pat. No. 5,800,749 issued Sep. 1, 1998; U.S. Pat. No.6,206,669 issued Mar. 27, 2001; U.S. Pat. No. 5,664,518 issued Sep. 9,1997; U.S. Pat. No. 6,543,469 issued Apr. 3, 2003; U.S. Pat. No.6,497,190 issued Dec. 24, 2002; or U.S. Pat. No. 6,911,252 issued Jun.28, 2005. For example, each of the composite preforms of the inventionmay be fabricated by the methods taught and disclosed in U.S. Pat. No.5,908,591 which steps comprise arranging a fabric layer and aconfiguration constrained against outward and defining a cavity betweentwo opposing surfaces of the fabric layer; dispensing a predeterminedamount of self-expanding, self-curable uncured foam into the cavity, thefoam expanding inhering in the cavity and a molding pressure determinedby the predetermined amount of the foam and thereby attaching itself tothe fabric layer to form the composite structure, the molding pressurecausing the expanding foam to substantially fill only enter stitches ofan inner portion of the fabric layer, without substantially penetratingan outer portion of the fabric layer; and, freeing the cured compositestructure from the constraint of the arranging step, the outer portionof the fabric layer of the composite structure being thereaftersubstantially completely saturated with a curable resin. The compositepreform is then ready for lamination to another structure in subsequentprocessing steps. The method may further comprise the step of attachingthe cured composite preform to another composite structure, such as thetop plate of the invention or the bottom plate of the invention, bybonding with adhesives or chemical bonding agents, by saturating theouter portion of the fabric layer of the cured composite structure witha curable resin and by applying a layer or layers of fabric over thecomposite preform and adjacent plate areas and also saturating the layeror layers with resin, or both.

The structural panel top half and structural panel bottom half may thenbe generally described as a plurality of structural preforms placed upona top plate and bottom plate, respectfully, and arranged in a spacing asdesired by the user which spacing may be, but is not necessarily,uniform, and in which the disposition of composite preforms may begenerally parallel and evenly spaced. The cross-sectional shape of thecomposite preforms may be, in one embodiment, trapezoidal as shown anddisclosed in the figures of the drawings but it is understood that it iswithin the scope of the invention that any other cross-sectional shapessuch as square, rectangular, triangular, polygon, or any othercross-sectional shape may comprise composite preforms of the invention.Referring now to the trapezoidal cross-sectional shape embodiment of theinvention, structural panel top half and structural panel bottom halfmay comprise an alternating cross sectional pattern of foam and airfilled trapezoids that are configured such that when the structuralpanel top half and structural panel bottom half are assembled togetherby, for instance, any structural adhesive known in the art, a unitarystructure comprising alternating trapezoidal voids and trapezoidal solidshapes filled with foam is created as shown in the exemplary embodimentdepicted in the figures of the drawings.

An embodiment of the structural composite panel may further be describedas having a top plate defined as a planer structure and having an uppersurface and an underneath surface, wherein the top plate is comprised ofa plurality of fiber layers saturated with resin and subsequently cured;a bottom plate defined as a planer structure and having an upper surfaceand a lower surface wherein the bottom plate is comprised of a pluralityof fiber layers saturated with resin and subsequently cured; a first setof at least one composite preforms having a foam core and covered in afabric saturated with resin and subsequently cured; a second set of atleast one composite preforms having a foam core and covered in a fabricsaturated with resin and subsequently cured; wherein the first set ofcomposite preforms are attached to the underneath surface of said topplate; and wherein the second set of composite preforms are attached tothe upper surface of the bottom plate; and wherein the first set ofcomposite preforms and the second set of composite preforms are attachedtogether, forming a structural composite panel. The first and second setof composite preforms may be trapezoidal in cross section, and theattachment of the first set of composite preforms to the underneathsurface of the top plate may occur at a large base of the preformtrapezoids; and the second set of composite preforms attachment to theupper surface of the bottom plate may also occur at a large base of thetrapezoids. The attachment of the first set of composite preforms andthe second set of composite preforms may occur at the small bases of thetrapezoids.

The structural panel top plate and structural panel bottom plate may befabricated by hand lamination, infusion, resin transfer molding assemblytechniques, or by any other means for creating a structural compositeplate as is known in the art.

The foam filled composite preforms of the invention may be fabricated byhand lamination, infusion, resin transfer molding assembly techniques,by the methods for continuously manufacturing a composite preform astaught and disclosed in any of the following documents: U.S. Pat. No.6,013,213, issued Jan. 11, 2000; U.S. Pat. No. 6,004,492 issued Dec. 21,1999, U.S. Pat. No. 5,897,818 issued Apr. 27, 1999; U.S. Pat. No.5,908,591 issued Jun. 1, 1999; U.S. Pat. No. 5,429,066 issued Jul. 4,1995; U.S. Pat. No. 5,800,749 issued Sep. 1, 1998; U.S. Pat. No.6,206,669 issued Mar. 27, 2001; U.S. Pat. No. 5,664,518 issued Sep. 9,1997; U.S. Pat. No. 6,543,469 issued Apr. 3, 2003; U.S. Pat. No.6,497,190 issued Dec. 24, 2002; and U.S. Pat. No. 6,911,252 issued Jun.28, 2005; or by any other technique known in the art for manufacturingcomposite structures.

Once fabricated, structural panel top half and structural panel bottomhalf may be bonded together to form a unitary completed structuralcomposite structural panel comprising a top plate, a bottom plate, and aseries of trapezoidally or otherwise-shaped voids and foam filled spacescovered by a fabric such as, for example fiberglass or carbon fiber, andsaturated with a resin which is subsequently cured. Structural panel topplate may be bonded to the structural composite preforms, and structuralpanel bottom plate may be bonded to the structural composite preforms.The resulting structural panel comprises a top plate, a bottom plate,and alternating trapezoidal boys and foam filled open spaces created bythe plurality of structural composite preforms. While it is within thescope of the invention that the structural composite preforms may bealigned in any orientation between the top and bottom plates, apreferred embodiment of the structural panel of the inventions intendedfor bridge decking applications comprises the structural compositepreforms disposed in a transverse direction to the longitudinal axis ofthe bridge structure, which may be, for instance, the direction oftravel of vehicles upon the bridge deck surface.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated into and form a partof the specification, illustrate one or more embodiments of the presentinvention and, together with the description, serve to explain theprinciples of the invention. The drawings are only for the purpose ofillustrating the preferred embodiments of the invention and are not tobe construed as limiting the invention. In the drawings:

FIG. 1 depicts an assembled perspective view of a preferred embodimentof a structural panel of the invention in which the top half and bottomhalf have been structurally bonded together forming a unitary structurecomprising alternating trapezoidally shaped voids and foam filledspaces, in which the foam filled spaces comprise composite preformscovered in fabric and saturated in resin which is subsequently cured.

FIG. 2 depicts a perspective view of the top half of the invention inwhich structural composite preforms, which are covered in fabric andsaturated resin which is subsequently cured, are disposed in parallelfashion upon a bottom surface of the top plate of the invention andbonded thereto by any structural adhesive or chemical bonding known inthe art.

FIG. 3 depicts a perspective view of the bottom half of the invention inwhich structural composite preforms, which are covered in fabric andsaturated in resin which is subsequently cured, are disposed in parallelfashion upon a top surface of the bottom plate of the invention andbonded thereto by any structural adhesive for chemical bonding known inthe art.

FIG. 4 depicts an expanded view of the assembled structural panelembodiment of the invention, more closely showing the structural bondingbetween composite preforms and between the composite preforms and thebottom surface of the top plate and top surface of the bottom plate ofthe invention.

FIG. 5 depicts a cross-sectional view of the assembled structural panelof the invention, more closely showing the structural bonds between thecomposite preforms, and showing the bonds between the composite preformsand the bottom surface of the top plate and top surface of the bottomplate of the invention.

FIG. 6 depicts an assembled perspective view of a plurality of thestructural panel panels of the invention in which the composite preformsare disposed transverse to the longitudinal axis of the resultingstructural panel assembly, which may also be the direction of travel forvehicles upon a bridge deck comprising structural panels of theinvention.

FIG. 7A depicts a perspective view of a bridge structure upon which aplurality of structural panels of the invention have been placed to forma continuous bridge deck, and showing a vehicle upon the bridge deck.

FIG. 7B depicts a cross section view of a bridge structure upon whichthe structural panels of the invention have been placed to form acontinuous bridge deck.

FIG. 8 depicts a perspective cross section view of an exemplarycomposite preform of the invention, showing the foam core surrounded bynon-woven fabric, which is in turn surrounded by a woven fabric havingfibers oriented in a +45 degree and an −45 degree orientation related toa longitudinal axis of the composite preform.

FIG. 9 depicts a perspective view of an exemplary fabric layer stack-upcomprising the top and bottom plates of the structural panel of theinvention.

FIG. 10 depicts a cross section view of an exemplary structural panel ofthe invention as being assembled from a top half and a bottom half,wherein the top half comprises a top plate attached to at least one butpreferably a plurality of composite preforms, and wherein the bottomhalf comprises a bottom plate attached to at least one but preferably aplurality of composite preforms, and wherein the composite preforms ofthe top half are bonded to the composite preforms of the bottom half,forming an exemplary structural panel of the invention.

FIGS. 11A and 11B depict a method and apparatus for forming non-planarembodiment of the structural panels of the invention which may beutilized to form crowned roadways, curved walkway covers, or any curvedstructural panel.

FIGS. 12A and 12B depict the assembly of a non-planar panel embodimentof the invention which may be utilized to form crowned roadways, curvedwalkway covers, or any curved structural panel.

FIGS. 13A and 13B depict an overlap fabric joint of the prior art inwhich tow ends are overlapped and wetted with resin to form a structure.These figures are for the purpose of explaining some of the advantagesof the method and apparatus of the invention.

FIG. 14A depicts a layer stack up of the prior art in which fabriclayers are overlapped and wetted with resin to form a structure. Thisfigure is for the purpose of explaining some of the disadvantages of themethod and apparatus of the prior art.

FIG. 14B depicts a layer stack up of the prior art in which fabriclayers are overlapped and wetted with resin to form a structure. Thisfigure is for the purpose of explaining some of the disadvantages of themethod and apparatus of the prior art.

FIG. 15 depicts the ability for structural panel halves of the inventionto be nested by receiving complementary surfaces for shipping so thatshipping volume required for the structural panel halves issignificantly minimized, leading to reduced shipping costs.

FIG. 16 depicts an alternate embodiment of the structural panel of theinvention having only one row of composite preforms.

DETAILED DESCRIPTION OF THE INVENTION

The invention generally comprises a structural panel that comprises aplurality of composite preforms that are attached to a top plate and toa bottom plate to form a structural panel top half and a structuralpanel bottom half. The structural panel top half and structural panelbottom half may be attached together to form a completed structuralpanel. The invention further comprises a method of manufacturing thestructural panel of the invention.

As used herein, the word “panel” or “structural panel” means a completedstructural panel that may be utilized in any orientation, and for anyapplication, as may be desired by the user. Thus, a completed structuralpanel of the invention may be used to provide decking for bridges,ramps, trestles, floors for buildings, or other horizontal, vertical orangled structures. In the exemplary application disclosed herein, oneintended use of the structural panel of the invention is that of deckingfor bridges. However it is to be understood the bridge deckingapplication is only one of many applications of the structural panel ofthe invention, and that the structural panels of the invention may beutilized in any number of applications and made be disposed in anyorientation as may be desired by a user to suit a particular purpose.Thus, for instance, the structural panels of the invention may beutilized to provide a vertical structure, horizontal structure, astructure that is oriented at any angle, and which may be used for anypurpose.

Referring now to FIG. 1, a perspective view of a structural panel of theinvention is depicted. Top plate 101 forms an upper surface ofstructural panel 050 of the invention. Open spaces 250 may be filledwith air and may run in the direction of arrow B through structuralpanel 050. Structural panel bottom half side plates 220 may optionallyform both sides of structural panel 050. Side plates 220 are optional:the structural panel of the invention may or may not comprise sideplates 220. Side plates 220 may be of a height that is substantiallyequal to the thickness of the combination of the top plate, thecomposite preforms 400 attached to the top plate 101, the bottom plate210, and the composite preforms 400 attached to said bottom plate. Foam260 may fill the composite preform interior space as indicated in thefigure and as further described below in the description ofmanufacturing composite preforms 400. Structural panel bottom plate 210forms a bottom surface of structural panel 050. Cabling, piping,conduit, and the like may traverse the structure through open spaces 250as desired by the user. Furthermore, open spaces 250 may be used foroptical and other inspection after manufacturing or after installationof the structural panels of the invention. This ability to inspect theinterior of the installed structural panel of the invention is asignificant advancement in the state of the art, as it is generallyimpossible to inspect the interior of the typical structural panels ofthe prior art, which may be fabricated, for example, from cement.Direction A is shown for reference to the other figures.

Referring now to FIG. 2, a perspective view of structural panel top half100 is depicted. In the exemplary embodiment shown, seven compositepreforms 400 are chemically bonded to a bottom surface of structuralpanel top plate 101 to form structural panel top half 100. It is to beunderstood that although seven composite preforms 400 are depicted inthe figure, any number of composite preforms may comprise the invention.So, for example, the invention may comprise any number of compositepreforms ranging from one to twenty or more. The number of compositepreforms, and the size of composite preforms 400, are determined by theuser of the system based upon the structural loads anticipated to beapplied to the structural panel of the invention in any particularapplication, such as bridge decking, ramp decking, and the like.Typically, the structural panel of the invention will comprise aplurality of composite preforms 400 and, typically, the compositepreforms 400 of the invention will be spaced equidistant from oneanother and will run parallel to one another as depicted in the variousfigures of the drawings. However, it is to be understood that anynumber, size, spacing between, and orientation or disposition of thepreforms may be utilized in the invention and therefore the invention isnot to be limited by the particular embodiment depicted in the figuresregarding same. Preform foam core 260 is shown for reference.

Referring now to FIG. 3, a perspective view of structural panel bottomhalf 200 is depicted. In the particular embodiment depicted in FIG. 3,seven composite preforms 400 are bonded to an upper surface ofstructural panel bottom plate 210. Bottom half side plates 220 mayoptionally form sides of structural panel bottom half 200. It is to beunderstood that although seven composite preforms 400 are depicted inthe figure, any number of composite preforms 400 may comprise theinvention. The number of composite preforms 400, and the size ofcomposite preforms 400, are determined by the user of the system basedupon the structural loads anticipated to be applied to the structuralpanel of the invention in any particular application, such as bridgedecking, ramp decking, and the like. Thus the structural panel of theinvention may comprise any number or size of preforms. Typically, thestructural panel of the invention will comprise a plurality of compositepreforms 400 and, typically, the composite preforms 400 of the inventionwill be spaced equidistant from one another and will run parallel asdepicted in the various figures of the drawings. However, it is to beunderstood that any number, size, spacing between, and orientation ordisposition of the preforms may be utilized in the invention andtherefore the invention is not to be limited by the particularembodiment depicted in the figures regarding same.

Is generally desirable, but not necessary, that structural panel tophalf and structural panel bottom half comprise the same number ofcomposite preforms.

Referring now to FIG. 4, an expanded perspective view of an end portionof the structural panel of the invention 050 is depicted. Structuralpanel top plate 101 may be bonded on its underneath side to compositepreforms 400 in areas 290 which form a composite preform-to-top-platebond. Any chemical adhesive or bonding agent may be utilized to bondstructural panel top plate 101 to composite preforms 400 in the areasdesignated 290. Structural panel bottom plate 210 may be bonded on itsupper surface to composite preforms 400 in areas 295 which form acomposite preform-to-bottom plate bond. Any chemical adhesive or bondingagent may be utilized to bond structural panel bottom plate 210 tocomposite preforms 400 in the areas designated 295. The compositepreforms 400 that are bonded to the top plate 101 may be bonded to thecomposite preforms 400 that are bonded to bottom plate 210 at the areasdesignated as 296. The structural panel of the invention 050 thuscomprises open spaces 250, which are channels that allow for insertionof optical and other inspection probes or equipment of an assembledstructure. These open spaces 250 thus enable on-site inspection ofstructures, such as, by example, and not by way of limitation, insertionof fiber optic probes in order perform visual inspection. The ability toperform such inspection internal to the structural panel is asignificant advantage of the structural panel of the invention.

Referring now to FIG. 5, an orthogonal cross-section of the structuralpanel 050 of the invention is depicted. This view provides across-section view of the various bonding surfaces of the structuralpanel 050 of the invention. Composite preforms 400 may be attached to anunderneath surface of top plate 101 at the areas designated by 290 usingany adhesive or chemical bonding material or processes known in the art.Likewise, composite preforms 400 may be attached to an upper surface ofthe bottom plate 210 at the areas designated as 295 using any adhesiveor chemical bonding material or processes known in the art. In thismanner, a first set of composite preforms 400 may be bonded to anunderneath surface of top plate 101, and likewise a second set ofcomposite preforms 400 are bonded to a top surface of the bottom plate210. The first set of composite preforms 400 may then be lined up withand placed upon the second set of composite reforms 400 that are bondedto a top surface of the bottom plate 210 as depicted in the figure. Thefirst set of composite preforms 400 may then be attached to the secondset of composite preforms 400 at the junctions shown as 296 in thefigure using any adhesive or chemical bonding material or processesknown in the art, thus creating a structural panel 050 of the invention.Open spaces 250 and preform foam cores 260 are shown for reference.

Referring now to FIG. 6 a plurality of structural panels 050 of theinvention are depicted as they may be oriented, for example, in anapplication in which the structural panels 050 of the invention areutilized to create the decking of a bridge, causeway, ramp, trestle, orother structure. It can be seen that a plurality of structural panels ofthe invention 050 may be disposed such that the composite preformscomprising the structural panel 050 run in a transverse direction to thelongitudinal axis A of the bridge, causeway, ramp, trestle or otherstructure. Orientation of the composite preforms comprising structuralpanel 050 as depicted in the figure are preferred, however, compositepreforms of the invention may run in any direction relative to thelongitudinal axis of the completed structure as may be desired by theuser. It is to be understood that the orientation of the compositepreforms depicted in FIG. 6 is exemplary of one of many orientationsthat are within the scope of the invention. Transverse direction B is apreferred direction in which the structural composite preforms 400 run.

Referring now to FIGS. 7A and 7B, an example of but one of many intendeduses of the composite structural panel of the invention is depicted. Inthe example shown, a plurality of structural panels of the invention 050are disposed upon a series of longitudinal bridge support beams 500,which may be, for example, comprised of cement as is known in the art.The number and cross sectional shape of longitudinal bridge supportbeams 500 depicted in the figure are exemplary only: any number oflongitudinal bridge support beams 500 may be present in any given bridgedeck application, and the longitudinal bridge support beams 500 may takeany cross section. Arrow A indicates the longitudinal axis of the bridgeand roadway. Arrow B indicates a preferred orientation of the compositepreforms 400 of the invention; i.e., transverse to the longitudinal axisA of the bridge and roadway. Thus a vehicle 502 may traverse a roadwaysurface 501 that is disposed on an upper surface of structural panels050 of the invention.

Referring again to FIG. 5, the composite preforms 400 of the inventionas depicted in the figures of the drawings are generally comprised of afoam core interior surrounded by an outer reinforcing fabric layer. Anon-woven fabric layer, such as a mat fiber layer, may also be attachedto the reinforcing fabric layer. Foam is attached to the nonwoven fabriclayer on the side of the nonwoven fabric layer opposite the reinforcingfabric by filling the interstices (pores) of the fabric layer with foamand allowing the expanding foam to fill the interstitial spaces of thefabric layer. The outer reinforcing fabric layer and nonwoven fabriclayer may then be saturated with resin which is subsequently allowed tocure creating a completed composite preform ready for assembly ontoeither a top plate or bottom plate of the invention. There are severalmethods suitable for fabricating composite preforms 400, but the methodof the present invention comprises as a preferred method the methods forcontinuous fabrication of a composite preform as taught and described inU.S. Pat. No. 5,897,818 to Lewit, and also the methods taught anddisclosed in U.S. Pat. No. 6,013,213, issued Jan. 11, 2000; U.S. Pat.No. 6,004,492 issued Dec. 21, 1999; U.S. Pat. No. 5,908,591 issued Jun.1, 1999; U.S. Pat. No. 5,429,066 issued Jul. 4, 1995; U.S. Pat. No.5,800,749 issued Sep. 1, 1998; U.S. Pat. No. 6,206,669 issued Mar. 27,2001; U.S. Pat. No. 5,664,518 issued Sep. 9, 1997; U.S. Pat. No.6,543,469 issued Apr. 3, 2003; U.S. Pat. No. 6,497,190 issued Dec. 24,2002; and U.S. Pat. No. 6,911,252 issued Jun. 28, 2005.

As used herein, “foam” means foams that are commonly formed using two ormore component parts which are mixed together immediately prior to thetime that the phone is to be used. Thus, “foam” means any foam materialused in the art of composite structure manufacture, and includes, forexample and not by way of limitation, polyurethane foam such as aself-expanding self-curing foam. Typically, such a self-rising,self-curing foam is a urethane foam commercially available from BASF,MOBAY, PPG and is typically an MDI-based rigid polyurethane foam(methylene-diphenyl-methane diisocyanate) using “hydrogenatedchlorofluorocarbons” (HCFe), water and/or CO2 as a blowing agent. Forexample the foam may be a two-part, self-expanding, self-curing urethanefoam in which the component parts are mixed together prior to use. Thus,“foam” includes all foams and includes, but is not limited to, the classof foams known as structural foams.

Alternatively, after the fabric layers have been applied to the foamsuch that the foam core is at least partially covered by, in a preferredembodiment, a nonwoven fabric layer that is in turn covered by an outerreinforcing fabric layer, the methods taught and described in U.S.Patent Publication No. US20140262011A1 may be utilized to “wet out” orsaturate the fabric layers with resin in a continuous fashion, whichresin may then subsequently be cured by any of the known curing means inthe art, or using the continuous cure methods taught and disclosed inU.S. Patent Publication No. US20140262011A1, creating a completecomposite preform ready for assembly onto either a top plate or bottomplate of the present invention. It is within the scope of the presentinvention that all the methods for continuously curing the saturatedcomposite preforms taught and disclosed in U.S. Patent Publication No.US20140262011A1 may be utilized to wet out and cure the compositepreforms and plates of the invention.

As used herein, unless otherwise defined, “fabric” means woven ornonwoven fabric material. Nonwoven fabric material, sometimes alsoreferred to as knitted fabric, is preferably a material such as, forexample, commercially available under the trade name Duraspun® fromJohns Manville. The nonwoven layer is generally a nonwoven fabriccomposed of continuous thermoplastic fiber, needle punched together toyield a felt-like fabric. In addition to fabrics like Duraspun®, othermaterial such as polyester staple mat glass fiber mat, as well as otherorganic and inorganic fiber mats and fabrics can be employed as thenon-woven fabric material. Reinforcing fiber is preferably, but notnecessarily, a woven directional reinforcing fiber layer of organic orinorganic structural reinforcing fibers such as, for example, glassfibers, carbon fibers, aramid fibers, such as those fibers availablefrom DuPont Corporation under the trade name Kevlar®, linearpolyethylene or polypropylene fibers such as is commercially availablefrom AlliedSignal Incorporated under the trade name Spectra®, orpolyester fibers. It should be understood that the phrase “reinforcingfiber” is meant to include any fiber which, when added to a compositematerial, enhances the structural properties of the material. The fiberscan be randomly oriented, or preferentially, they can be oriented in oneor more directions. While a number of specific types of materials havebeen given for use as the reinforcing fiber layer, it will beappreciated by those of ordinary skill in the art that other equivalenttype reinforcing fiber layers can be employed in the practice of theinvention.

As used herein, unless otherwise defined, “resin” means any matrix orother material that is used to coat or saturate the fabric layers of afiber-reinforced composite structure or preform. Such resins include butare not limited to polymers (orthophthalic, isophthalic or otherwise),polyester resins, vinyl ester resins, epoxy resins, phenolic and anyother resin known in the art of composite structure manufacture. As usedherein, “resin” or “resins” also includes any resin that is cured orpolymerized by application of chemical accelerants or catalysts, light(regardless of wavelength), heat, electron beam cure that may utilize,for example, high energy electrons or X rays such as ionizing radiation,or any other type of cure process or materials known in the art. Lightcure, as used herein, also means “light-activated”, and includes alllight curable resins including but not limited to one-part translucentpolymers that cure when exposed to a specific light spectrum. When theword “light” is used herein, it refers to light energy of an opticalspectrum that is matched to the light curable resin it is being used tocure. “Cure on demand” resins mean any resin that does not self-cure:typically cure on demand resins are cured by application of someexternal energy such as heat, light, ionizing radiation or any otherenergy source.

As used herein, “cure” and “cured” means any method for curing resinsknown to persons of reasonable skill in the art such as heat cure, timecure, light cure, chemical cure and all other methods for curing resins.“Cure” and “cured” also means all methods for curing taught anddisclosed in United States Patent Application Publication No.US20140262011A1, published on Sep. 18, 2014 and also includes allmethods for co curing taught and disclosed in United States PatentApplication Publication No. US20140199551, CO-CURED GEL COATS,ELASTOMERIC COATINGS, STRUCTURAL LAYERS, AND IN-MOLD PROCESSES FOR THEIRUSE.

As referred to herein, a “unidirectional warp fabric” is a woven fabricin which the majority of fibers run in one direction, which is thedirection, or warp, of the roll upon which the fabric is disposed priorto use.

Manufacturing the Composite Preforms 400

One method, although not preferred, for manufacturing the compositepreforms of the invention is to use the traditional mold constructiontechnique. Elongated molds of desirable cross section, such astrapezoidal, rectangular, triangular, square or any other crosssectional shape desired, which can be lined with fabric layers asdescribed above, may be provided. The molds are then injected with foamwhich has been formed by mixing the proper ratio of constituent parts.The component foam parts typically comprise a blowing agent which iscombined with a resin. After these steps, the outer reinforcing fabriclayer and nonwoven fabric layer may then be saturated with resin whichis subsequently allowed to cure, creating a composite preformed whichmay then be cut to length. The composite preform is then ready forassembly onto either a top plate or bottom plate of the invention asdescribed elsewhere herein. In this manner, the structural preforms ofthe invention may be fabricated. However, this is not a preferredtechnique for fabrication of the structural preforms of the inventionbecause this method the fabrication of composite preforms istime-consuming and does not lend itself to rapid production rates suchas are required in an efficient assembly line.

A preferred method for continuously fabricating the composite preformsof the invention is the process described in detail in U.S. Pat. No.5,897,818 to Lewit (the “818 patent). Generally, a conveyor system,roller-fed fabric or fabrics, and a forming die are used to assemble thecomposite preform as taught and described in the '818 patent. An upperfabric guide is provided to aid in smoothing the fabric web and properlypositioning same as it passes into of the forming die. Foam is injectedinto, or slightly before, the forming die. The foam expands intointerstitial spaces in the fabric layer closest to the foam as thefabric layers are fed through the forming die, such that a compositepreform exits the exit side of the forming die that is covered at leastpartially in one or more fabric layers, the innermost of this isattached to the expanded foam forming the foam core of the compositepreform. The composite preform may then be cut to length as described inthe '818 patent, or may be cut by any other means including by hand. Thefinal, cut-to-length composite preform may then be saturated with resin,which may then be subsequently cured, by any method known in the art,including the methods of wetting out, or saturating the fabric layer orlayers of the composite preform, and curing out taught and disclosed inU.S. Patent Application Publication No. US20140262011A1.

Referring now to FIG. 8, the composite preforms comprising the inventionmay comprise any foam, any fabric, any number of layers of fabric, andany orientation of fibers as may be desired by a user. A presentlypreferred embodiment of the composite preforms of the invention may be,but is not necessarily, produced by the process described in detail inthe '818 patent, is depicted in FIG. 8. Included within the scope of themethod of the present invention are all methods for continuouslymanufacturing a composite preform taught and disclosed in the '818patent. In a preferred embodiment of the structural panel of theinvention, composite preform foam core 260 is surrounded by non-wovenmat fabric 261, which may be a polyester felt mat, which in turn may besurrounded by a 24 ounce per square yard fabric layer 262 comprisingfiber layers oriented in an +45 and −45 degree orientation as related tolongitudinal axis B of the composite preform 400.

Manufacturing the Top Plate 101 and Bottom Plate 210 of the Invention

The top plate depicted as item 101 in the figures of the drawings, andthe bottom plate, depicted as item 210 in the figures of the drawings,may each be fabricated by using manufacturing processes known in the artfor fabricating laminated plates comprised of at least one, butpreferably a plurality, of fabric layers that have been impregnated withresin which is subsequently cured.

Preferably, but not necessarily, the fabric layers comprising top plate101 and bottom plate 210 may be defined as a combination of layers offabric, in which multiple combined layers comprising a layer of wovenfabric such as, for example, 18 ounce per square yard warpunidirectional E-glass stitched to a layer 1.0 ounces per square footchopped strand mat (“CSM”) fabric. The CSM fabric provides aninter-layer spacing between the layers of warp unidirectional glass.This spacing creates a separation between the layers of warpunidirectional glass which serves to reduce shear strain forcesdeveloped in the layers of warp unidirectional glass when a plate of theinvention is subjected to forces such as a bending force. This advantageof the invention over the prior art is depicted in FIGS. 14A and 14B.Referring now to FIG. 14A, a plate of the prior art constructed of twolayers of woven fabric which have been impregnated with a resin which issubsequently cured is depicted. A first woven layer I is thus connectedto a second woven layer J by the resin between them L. When a prior artplate constructed thusly experiences forces causing it to bend as shownin FIG. 14A, shear strain develop in the resin layer L which is theattachment between layers I and J. Typically, such plates areconstructed by overlaying fabric layers I and J, and then impregnatingthem with resin simultaneously during a wet out process, which is thenfollowed by a resin curing process. Since layers I and J are overlaid,the distance Ml between them may be very small. This can lead toextremely high shear stress or strain values in the connecting resinlayer L, which will cause failure in the resin layer L and eventuallywill propagate when the plate is subjected to further or continuedbending loads, causing structural failure of the plate.

In contrast to the prior art panel shown in FIG. 14A, one embodiment ofthe plates of the invention in which woven fabric layers I and J areseparated by an interposing layer of non-woven fabric K as depicted inFIG. 14B. The non-woven fabric layer K, which may be the non-woven layer261 of FIG. 9, may be stitched to the woven fabric layers I and J whichmay be the woven fabric layers 270 of FIG. 9. The non-woven fabric layerK serves to increase the separation between woven layers I and J. Thus,when a plate of the invention is subjected to the same bending forces asthe example of FIG. 14A, the magnitude of the shear stress or straindeveloped in resin layers L1 and L2 is substantially less than the shearstress or strain developed in resin layer L in the example of FIG. 14A.This means that an embodiment of the invention which comprises one ormore combined layers as depicted in FIG. 14B will experience less shearstress or strain in its resin layers than plates of the prior art, andwill be able sustain greater applied force than plates of the prior art.Thus the layer stack sequence depicted in FIG. 14B and further in FIG. 9is optimized on both a local and global level for reducing shear strainin the composite structure.

Referring now to FIG. 9, an exemplary preferred embodiment of each oftop plate 101 and bottom plate 210 is depicted in which the variousfabric layers are described. A preferred embodiment of top plate 101 maycomprise a plurality of groups of fabric layers, each group comprisingat least one but preferably a plurality of woven fabric layers in thegroup having their unidirectional fibers running in a similar directionand each woven fabric layer in the group separated by a non-woven fabriclayer, and each successive fabric layer group having the woven fabriclayers unidirectional fibers running at 90° to the unidirectional fibersin the woven fabric layers of the adjacent groups. Thus, a first group Rof fabric layers may comprise woven fabric layers 270 separated bynon-woven fabric layers 261 and arranged such that the direction oftheir unidirectional fibers is along the axis indicated by arrow A;followed by a second group S of fabric layers comprising woven fabriclayers 270 separated by non-woven fabric layers 261 and arranged suchthat their unidirectional fibers are oriented along the axis indicatedby arrow B which may be transverse to, or oriented at 90° to, directionA; followed by a third group T of woven fabric layers 270 separated bynon-woven fabric layers 261 and disposed such that their unidirectionalfibers are oriented along the axis indicated by arrow A, and so on. Thisalternating pattern of groups of fabric layers comprising woven fabriclayers 270 separated by non-woven fabric layers 261 and arranged suchthat their unidirectional fibers are oriented in either the direction ofA or B, with each group alternating the direction of theirunidirectional fibers, may be comprised of any number of woven fabriclayers 270 per group, each woven fabric layer 270 separated by anon-woven layer 261, and the plates of the invention may comprise anynumber of groups. It is not necessary that the top and bottom plates ofthe invention comprise the same number of fabric layers, fabric groups,or fabric layers per group. In a preferred embodiment of top plate 101,each woven fabric layer 270 may comprise any fabric weight but ispreferably 18 ounce per square yard warp unidirectional E-glass and maybe separated by a non-woven, or chopped stranded mat, fabric layer 261comprising any fabric weight but is preferably 9.0 ounces per squareyard (or 1 ounce per square foot). The fabric layers may be stitchedtogether. The assembly of fabric layers comprising the top and bottomplates is then saturated with a resin which is subsequently cured toform a preferred embodiment of top plate 101 or bottom plate 210 of theinvention. Although this is the preferred embodiment for the fabricelements comprising top plate 101 and bottom plate 210, any othercombination or orientation of fabrics may comprise the top and bottomplates of the invention. However, the specific fabrics identified hereinprovide for maximum continuity of the unidirectional fibers, while themat layers control the fiber content to maximize fatigue performanceunder the dynamic traffic load as may be expected in many structuralapplications including but not limited to bridge decking applications.These preferred exemplary embodiments of top plate 101 and bottom plate210 typically result in a top plate 101 thickness of between 9/16 inchesand ¾ inches, and a bottom plate 210 thickness of between ⅜ inches and ½inch; however, any number of fabric layers may comprise the top plate101 and bottom plate 210 layers, and thus the thickness of top plate 101and bottom plate 210 by be determined by the numbers of fabric layerschosen by the user to fabricate these structural members and aretherefore variable as desired by the use. The layers of fabric may bestitched together.

Top plate 101 and bottom plate 210, depicted as rectangular in thefigures of the drawings, may take any outline or shape desired and maybe any cross-sectional thickness desired as may be required by theparticular application for which the structural panel is intended to beused. In the exemplary embodiments described herein, top plate 101 andbottom plate 210 are shown to be rectangular in shape. However, it is tobe understood that these are exemplary depictions only and that topplate 101 and bottom plate 210 may take any shape, or be anycross-sectional thickness as may be required by a specific applicationof the structural panel of the invention.

While woven fabric layers 270 may be any fabric, they are preferably,but not necessarily, comprised of unidirectional warp fabric layersoriented with their unidirectional fibers running as shown in FIG. 9.These woven fabric layers 270 are preferably comprised of a continuousfabric layer, or, other words, there are no overlapping joints asdepicted in FIGS. 13A and 13B in which two pieces of fabric are joinedto create a single layer 270. Such overlapping joints, which may becreated by overlaying a first fabric layer E onto a second fabric layerF by placing fabric layer E onto fabric layer F in the direction ofarrow H and then wetting the joint with resin, followed by curing theresin, are sometimes used in the prior art to attach fabric to astructure, and are weak points in the structure due to the discontinuityof fibers across the joint area D. In such construction usingoverlapping joints, the resin G between fabric layer E and F must carryall loads applied to the structure because of the discontinuity of thefibers at the joint. Preferred embodiments of the invention have no suchoverlapping joints in any layer; the preferred embodiments of theinvention avoid overlapping joints by utilizing continuous runs offabric in the buildup of the layers.

Assembling the Structural Panel Top Half 100 and Bottom Half 200

Referring now to FIG. 10 an exemplary method and assembly procedure forassembling the structural panel top half and structural panel bottomhalf are now described.

Still referring to FIG. 10, top plate 101 may be oriented as shown and aplurality of composite preforms 400 may be placed in contact with anunderneath surface of top plate 101 as shown in FIG. 10. Structuralcomposite preforms 400 may be bonded to the underneath surface of topplate 101 in the areas depicted as 290 in FIG. 10. Each of the compositepreforms 400 may be attached to the underneath surface of top plate 101by any means known in the art but preferably are adhesively orchemically bonded using any known adhesive or chemical bonding agentknown in the structural composites arts. Additionally, compositepreforms 400 may be attached to the underneath surface of top plate 101by adding fabric layers placed over composite preforms 400 such thatthey overlay composite preforms 400 and also overlay a portion of theunderneath surface of top plate 101 on each side of each compositepreform 400, saturating said fabric layers with resin, and subsequentlycuring the resin. Such fabric layers, once saturated and cured, serve tonot only bond the composite preforms 400 to the underneath surface oftop plate 101 but also serve to strengthen structural panel top half100. Any number of fabric layers may be utilized for the attachment ofcomposite preforms 400 to the underneath surface of top plate 101. Inthis manner, structural panel top half 100 is fabricated in thisexemplary but preferred embodiment of the method of the invention. Anysuitable series of steps resulting in the attachment of compositepreforms 400 to the underneath surface of top plate 101 described hereinmay be utilized in the method of the invention. It is to be understoodthat the specific method and series of steps described herein isexemplary of just one of many embodiments of the method of theinvention.

Still referring to FIG. 10, bottom plate 210 may be oriented as shownand a plurality of composite preforms 400 may be placed in contact withand on top of an upper surface of bottom plate 210 as shown in FIG. 10.Structural composite preforms 400 may then be bonded to the uppersurface of top plate 101 in the area respected as 295 in FIG. 10 each ofthe composite preforms 400 may be attached to the upper surface of thebottom plate 210 by any means known in the art but preferably areadhesively or chemically bonded using any known adhesive or chemicalbonding agent known in the structural composites arts. Additionally,composite preforms 400 may be attached to the upper surface of bottomplate 210 by adding fabric layers placed over composite preforms 400such that they overlay composite preforms 400 and also overlay a portionof the upper surface of bottom plate 210 on each side of each compositepreform 400, saturating said fabric layers with resin, and subsequentlycuring the resin. Such fabric layers, once saturated and cured, serve tonot only bond the composite preforms 400 to the underneath surface ofbottom plate 210 but also serve to strengthen structural panel bottomhalf 200. Any number of fabric layers may be utilized for the attachmentof composite preforms 400 to the upper surface of bottom plate 210. Inthis manner, structural panel bottom half 200 is fabricated in thisexemplary but preferred embodiment of the method of the invention. Anysuitable series of steps resulting in the attachment of compositepreforms 400 to the upper surface of bottom plate 210 may be utilized inthe method of the invention. It is to be understood that the specificmethod and series of steps described herein is exemplary of just one ofmany embodiments of the method of the invention.

Assembling the Structural Panel of the Invention

Still referring to FIG. 10, structural panel top 100 and structuralpanel bottom half 200 may be assembled together in the following mannerto form the structural composite panel of the invention. Structuralpanel top 100 may be placed upon structural panel autumn half 200 asdepicted by the direction lines D in FIG. 10, forming a bonding joint296 between surfaces of the composite preforms of the structuralcomposite panel top half 100 and the composite preforms of structuralcomposite panel bottom half 200. Structural composite panel top half 100and structural composite panel bottom half 200 may be attached togetherusing any chemical bonding agent or adhesive known in the structuralcomposite arts to form a completed structural composite panel of theinvention as is shown in cross-section in FIG. 5 and an perspective viewin FIGS. 1 and 4. It should be noted that structural panel bottom halfside plates 220 are optional and may be present in an alternateembodiment of the invention. Thus the structural panel of the inventionin various alternate embodiments may, or may not, comprise side plates220.

It is to be understood that the application of curable resin(s) andother coatings, such as gel coat, may be accomplished in any order orsequence and may be subsequently cured using any process known in theart. For example, the invention comprises the methods and processes forco-curing resins, gel coats and other materials taught and described inUnited States Patent Application Publication No. US20140199551, CO-CUREDGEL COATS, ELASTOMERIC COATINGS, STRUCTURAL LAYERS, AND IN-MOLDPROCESSES FOR THEIR USE, published Jul. 17, 2014. The co-curing methodstaught in this U.S. pre-grant patent publication provide toughness,flexibility, chip and crack resistance without sacrificing good adhesionto structural layers of resin-saturated fabrics.

Fabrication and Assembly of a Non-Planer Structural Panel Embodiment

Referring now to FIGS. 11A and 11B, an alternate embodiment of theinvention is depicted. In this embodiment, a support structure 600having a desired surface shape 601 may be used to shape pre-curedelements of the structural panel 050 such as plates 101 or 102, orcomposite preforms 400, such that they take a desired shape, which maybe any shape. The uncured elements, which are pliable and flexible to adegree, may be placed over and drawn down onto surface 601 using methodsknown in the art such as vacuum bagging. The elements of the structuralpanel 050 such as plates 101 or 102, or composite preforms 400, may bewetted with resin and cured using any process known in the art, thusthem to take on the desired shape 601 which may be any shape desired bya user but is shown as curved surface for illustrative purposes in FIGS.11A and 11B. The resulting shaped elements may then be assembledtogether chemically bonded together to form a structural panel of theinvention that has a desired shape as depicted in FIGS. 12A and 12B.

Referring now to FIGS. 12A and 12B, plates 101 or 102, and compositepreforms 400, which have been formed over support structure 600 (notshown in FIGS. 12A and 12B, but shown in FIGS. 11A and 11B) so that theycomprise the desired shape 601 are motivated together in the directionof arrow A where they may be chemically bonded together to form acompleted panel having a desired shape 601. In this manner, curved orshaped panels of invention may be manufactured by pre-shaping theelements of the structural panels and assembling them together to form astructural panel of the invention comprising a desired shape. Suchcurved embodiments of the structural panel of the invention may be usedto form crowned roadways which shed water as may be required forvehicles to safely traverse a bridge or other roadway structure, or maybe used to form roof panels, coverings for walkways, and the like.

Referring now to FIG. 15, a first and second nested set of structuralpanel top halves, P and Q, are depicted, in which the complimentarysurfaces created by the structural composite preforms 400 are of suchdimension so as to allow a first structural panel top halve 101 and asecond structural panel top half 101 to nest together as shown. Thepreforms 400 comprising the top plate and the preforms 400 comprisingthe bottom plate may form complimentary surfaces such that a top platemay nest within a bottom plate when a top plate is inverted andmotivated onto a bottom plate. Thus, the complimentary surfaces of thestructural panel halves allow for nesting of panel halves duringshipment, reducing shipping volume and therefore also reducing shippingcosts. In this embodiment, structural panel halves may efficiently beshipped to a construction site, such bridge, building, or otherconstruction site, and assembled in place using, for example, chemicalbonding. In this manner, the shipping volume required may be fiftypercent (50%) the shipping volume of a structural panel that does notcomprise complimentary surfaces, which allows significant cost and timesavings for construction of bridges, buildings and other structures.

The composite preforms 400 of the invention need not be of uniformheight or width, which is to say their cross sectional dimensions mayvary along their length.

Referring now to FIG. 16, a further alternate embodiment of thestructural panel 051 of the invention is depicted. One or more, andpreferably a plurality, of composite preforms 400 may be attached to anupper surface of bottom plate 210 at attachment surfaces 702, which maybe large bases of trapezoidally shaped preforms, by any means known inthe art but preferably by chemical bonding. Likewise, composite preforms400 may be attached to an underneath surface of top plate 210 atattachment surfaces 701, which may be small bases of trapezoidallyshaped preforms, by any means known in the art but preferably bychemical bonding. Open spaces 703 run between composite preforms 400 andprovide for easy inspection of the interior spaces of the structuralpanels by any means known in the art for inspection of structures suchas visual inspection using fiber optic scopes and the like.

Although a detailed description as provided in the attachments containsmany specifics for the purposes of illustration, anyone of ordinaryskill in the art will appreciate that many variations and alterations tothe following details are within the scope of the invention.Accordingly, the following preferred embodiments of the invention areset forth without any loss of generality to, and without imposinglimitations upon, the claimed invention. Thus the scope of the inventionshould be determined by the appended claims and their legal equivalents,and not merely by the preferred examples or embodiments given.

INDUSTRIAL APPLICABILITY

A composite structural panel and method of fabricating and manufacturingsame comprises a top panel and a bottom panel separated by and attachedto at least one, but preferably a plurality, of structural compositepreforms which may be fabricated by a continuous manufacturing processand may be saturated by resin using a continuous wetting process. Thecomposite preforms may take any cross sectional shape but are preferablytrapezoidal. The top and bottom panels may be fabricated from aplurality of layers of woven fabric layers and non-woven fabric layerswhich are saturated with a resin that is subsequently cured using cureprocesses known in the art.

The composite structural panel of the invention is usable as a flatstructural member for use as bridge decking, ramps, trestles, roofstructures, floor structures, wall structures, and any applicationrequiring a structural panel, or, in alternative embodiments, may befabricated and assembled in any desired shape, such as a curved shape,as may be required for a particular structural application. Thus, curvedembodiments of the structural panel of the invention may be used to formcrowned roadways which shed water as may be required for vehicles tosafely traverse a bridge or other roadway structure, or may be used toform roof panels, coverings for walkways, and the like.

Cabling, piping, conduit, and the like may traverse the structurethrough open spaces in the panels of the invention as desired by theuser. Furthermore, the open spaces of the invention may be used foroptical and other inspection after manufacturing or after installationof the structural panels of the invention. This ability to inspect theinterior of the installed structural panel of the invention is asignificant advancement in the state of the art, as it is generallyimpossible to inspect the interior of the typical structural panels ofthe prior art, which may be fabricated, for example, from cement.

The complimentary surfaces of the structural panel halves allow fornesting of panel halves during shipment, thus reducing shipping volumeand therefore also reducing shipping costs. In this embodiment,structural panel halves may efficiently be shipped to a constructionsite, such bridge, building, or other construction site, and assembledin place using, for example, chemical bonding.

The composite preforms comprising the invention may be manufactured bycontinuous manufacturing processes, enabling rapid manufacturing,reducing lead time for production of panels, and allows for common crosssections of preforms to be pre-fabricated for use in manufacturingstructural composite panels of the invention.

The structural composite panels of the invention enable the fabricationof structures are not susceptible to corrosion, rust or otherdegradation suffered by metals structures, and further are notsusceptible to the degrading effects of galvanic corrosion. Thepreferred embodiments of the structural composite panels of theinvention contain no metallic components.

1-29. (canceled)
 30. A structural composite assembly comprising: a topstructural panel comprising: a top plate having an upper surface and anunderneath surface, wherein the top plate is comprised of a plurality offiber layers saturated with resin and subsequently cured; and a firstplurality of composite preforms attached to the underneath surface ofthe top plate, each composite preform comprising a foam core covered ina fabric, wherein the foam has expanded into interstitial spaces in thefabric, and wherein the fabric has been saturated with resin which hasbeen subsequently cured; and a bottom structural panel comprising: abottom plate having an upper surface and a lower surface, wherein thebottom plate is comprised of a plurality of fiber layers saturated withresin and subsequently cured; and a second plurality of compositepreforms attached to the upper surface of the bottom plate, eachcomposite preform comprising a foam core covered in a fabric, whereinthe foam has expanded into interstitial spaces in the fabric, andwherein the fabric has been saturated with resin which has beensubsequently cured.
 31. The structural composite assembly of claim 30,wherein the top structural panel and the bottom structural panel arenested together such that the first plurality of composite preforms isreceived between the second plurality of composite preforms.
 32. Thestructural composite assembly of claim 30, wherein: each of the firstplurality of composite preforms is trapezoidal in cross section with alarge base and a small base, the large bases being attached to theunderneath surface of the top plate; and each of the second plurality ofcomposite preforms is trapezoidal in cross section with a large base anda small base, the large bases being attached to the upper surface of thebottom plate.
 33. The structural composite assembly of claim 32, whereinthe top structural panel and the bottom structural panel are nestedtogether such that the small bases of the first plurality of compositepreforms are received between the large bases of the second plurality ofcomposite preforms.
 34. The structural composite assembly of claim 32,wherein the top structural panel and the bottom structural panel arenested together such that oblique side surfaces of the first pluralityof composite preforms compliment oblique side surfaces of the secondplurality of composite preforms.
 35. The structural composite assemblyof claim 30, wherein the number of the first plurality of compositepreforms in the top structural panel is the same as the number of thesecond plurality of composite preforms in the bottom structural panel.36. The structural composite assembly of claim 30, wherein the pluralityof fiber layers of the top and bottom plates each comprises woven fabriclayers and non-woven fabric layers.
 37. The structural compositeassembly of claim 30, wherein the plurality of fiber layers of the topand bottom plates each comprises woven fabric layers separated by aninterposing non-woven fabric layer.
 38. The structural compositeassembly of claim 30, wherein the structural composite assembly is ahorizontal floor having a longitudinal axis, the first and secondplurality of composite preforms running in a transverse directionrelative to the longitudinal axis.
 39. The structural composite assemblyof claim 30, wherein: the first plurality of composite preforms arespaced from one another and run parallel to one another; and the secondplurality of composite preforms are spaced from one another and runparallel to one another.
 40. The structural composite assembly of claim30, wherein the fabric of the first and second plurality of compositepreforms comprises an inner non-woven fabric layer adjacent to the foamcore and an outer reinforcing fabric layer.
 41. The structural compositeassembly of claim 30, wherein the fabric of the first and secondplurality of composite preforms is saturated with resin and subsequentlycured.
 42. The structural composite assembly of claim 30, wherein: thefirst plurality of composite preforms is attached to the underneathsurface of the top plate with cured resin; the second plurality ofcomposite preforms is attached to the upper surface of the bottom platewith cured resin.
 43. A structural composite assembly comprising: a topplate having an upper surface and an underneath surface, wherein the topplate is comprised of a plurality of fiber layers saturated with resinand subsequently cured; a first plurality of composite preforms attachedto the underneath surface of the top plate, each composite preformcomprising a foam core covered in a fabric, wherein the foam hasexpanded into interstitial spaces in the fabric, and wherein the fabrichas been saturated with resin which has been subsequently cured; and asecond plurality of composite preforms positioned between the firstplurality of composite preforms, each composite preform comprising afoam core covered in a fabric, wherein the foam has expanded intointerstitial spaces in the fabric, and wherein the fabric has beensaturated with resin which has been subsequently cured.
 44. Thestructural composite assembly of claim 43, wherein: each of the firstplurality of composite preforms is trapezoidal in cross section with alarge base and a small base, the large bases being attached to theunderneath surface of the top plate; and each of the second plurality ofcomposite preforms is trapezoidal in cross section with a large base anda small base.
 45. The structural composite assembly of claim 44, whereinthe small bases of the first plurality of composite preforms arereceived between the large bases of the second plurality of compositepreforms.
 46. The structural composite assembly of claim 44, whereinoblique side surfaces of the first plurality of composite preformscompliment oblique side surfaces of the second plurality of compositepreforms.
 47. The structural composite assembly of claim 43, furthercomprising a bottom plate having an upper surface coupled to the secondplurality of composite preforms and a lower surface, wherein the bottomplate is comprised of a plurality of fiber layers saturated with resinand subsequently cured.
 48. A method for manufacturing a structuralcomposite assembly comprising: providing a top plate comprising aplurality of fabric layers; providing a bottom plate comprising aplurality of fabric layers; providing a first and a second plurality ofcomposite preforms, each composite preform having a core comprised ofexpanding foam and a fabric layer, wherein the expanding foam hasexpanded into interstitial spaces in the fabric layer; arranging thefirst plurality of composite preforms adjacent to an underneath surfaceof the top plate; arranging the second plurality of composite preformsadjacent to an upper surface of the bottom plate; saturating the fabriclayers with resin; and curing the resin.
 49. The method of claim 48,wherein the saturating and curing steps are performed before thearranging steps.
 50. The method of claim 48, wherein each compositepreform is trapezoidal in cross section and has a large base, a smallbase, and oblique sides, the large bases of the first plurality ofcomposite preforms being arranged adjacent to the underneath surface ofthe top plate and the large bases of the second plurality of compositepreforms being arranged adjacent to the upper surface of the bottomplate.